How can I define material properties that depend on solution variables in CFX 11.0?
A user may define material properties that depend on solution variables (e.g. Temperature) by defining a user fuction or a polynomial: FUNCTION: sh_pol Option = Interpolation Option = One Dimensional Argument Units = [K] Result Units = [J kg^1 K^1] INTERPOLATION DATA: Data Pairs = 293.15,400,373.15,401,473.15,402,523.15,403.5,573.15,404,623.15,404.5 ,673.15,405 Extend Max = Off Extend Min = Off END and using this function to define density, viscosity, specific heat, thermal conductivity etc. When specific heat is defined as a function, the code creates a table for enthalpy h=f(T). By defaults the table range of temperature is between 100 K and 5000K. Therefore, the function/polynomial that defines specific heat (Cp) has to cover the same range. If the range over which Cp is defined is narrower, than the range has to be included in the definition of material properties: MATERIAL: material1 Material Group = User Option = Pure Substance Thermodynamic State = Solid PROPERTIES: Option = General Material TABLE GENERATION: Minimum Temperature = 300 [K] Maximum Temperature = 650 [K] ENDEQUATION OF STATE: Density = 870 [kg m^3] Molar Mass = 68.0 [kgkmol^1] Option = Value END SPECIFIC HEAT CAPACITY: Option = Value Reference Temperature = 350.0 [K] Specific Heat Capacity = sh_pol(T) Specific Heat Depends On = Temperature END THERMAL CONDUCTIVITY: Option = Value Thermal Conductivity = 500 [W m^1 K^1] END END If this is neglected, the code will generate an error massage and stop. **** Entered By: dsclarke @ 05/09/2007 03:10 PM **** 

